It is common practice to provide location information of a portable communication terminal, as an information delivery service in a mobile communication network. This location information is acquired by transmitting a request from the portable communication terminal to a location information calculating server to calculate or manage the location information about the portable communication terminal.
In mobile communication, transmission/reception of data between the portable communication terminal and a communication partner equipment such as a content server is performed using a user channel such as a speech channel, while transmission/reception of control data for controlling communication on the user channel is performed using a control channel different from the user channel (e.g., reference is made to Patent Document 1). The foregoing transmission/reception of the location information between the portable communication terminal and the location information calculating server is also carried out similarly using the user channel.
Patent Document 1: Japanese Patent Application Laid-Open No. 10-79700